Control system for vehicle

Abstract

A control system for a vehicle includes an electronic control unit. The electronic control unit is configured to i) calculate a target supercharging pressure of an intake air such that, when an internal combustion engine is operated through the homogeneous charge compression ignition, the internal combustion engine achieves a required output while satisfying a predetermined requirement, ii) control an output of the internal combustion engine such that the output approaches the required output in accordance with an actual supercharging pressure in process of changing the actual supercharging pressure to the target supercharging pressure that is achieved by a supercharger, and iii) control a rotary machine such that an output of the rotary machine compensates for part or all of a differential output between the required output and the output in process of changing the actual supercharging pressure to the target supercharging pressure.

Description

[0001]INCORPORATION BY REFERENCE[0002]The disclosure of Japanese Patent Application No. 2016-069633 filed on Mar. 30, 2016 including the specification, drawings and abstract is incorporated herein by reference in its entirety.BACKGROUND1. Technical Field[0003]The present disclosure relates to a control system for a vehicle including an internal combustion engine that is able to perform homogeneous charge compression ignition operation, a supercharger, and a rotary machine that is able to transmit power to a drive wheel.2. Description of Related Art[0004]There is well known a vehicle including an internal combustion engine (hereinafter, referred to as HCCI engine) that is able to perform homogeneous charge compression ignition (HCCI) operation (hereinafter, referred to as HCCI operation) and a supercharger that supercharges intake air into the HCCI engine. This is, for example, a vehicle described in Japanese Patent Application. Publication No. 2008-202520 (JP 2008-202520 A). JP 2008...

AI Technical Summary

Benefits of technology

This patent is about a control system for a vehicle that can handle changes in engine output when using a supercharging system. The system restricts shifting of the transmission to prevent decreased driver comfort caused by changes in output. This ensures the vehicle operates within the range of the supercharging system, resulting in better performance.

Problems solved by technology

Incidentally, supercharging has a delay in response.

For this reason, if a supercharging pressure is increased to a target supercharging pressure so as to inhibit abnormal combustion in the HCCI engine in changing the HCCI engine to a high load side by, for example, increasing fuel, it may not be possible to appropriately inhibit abnormal combustion in a period until the supercharging pressure becomes the target supercharging pressure.

Alternatively, if the supercharging pressure is decreased to a target supercharging pressure so as to inhibit a misfire in the HCCI engine in changing the HCCI engine toward a low load side by, for example, reducing fuel, it may not he possible to appropriately inhibit a misfire in a period until the supercharging pressure becomes the target supercharging pressure.

With the control system according to this aspect, the driver tends to experience a feeling of strangeness if actual driving force changes as a result of a change of a request from the hybrid system, which is not caused by driver's operation.

With the control system according to this aspect, the driver tends to experience a feeling of strangeness if actual driving force decreases as a result of a delay of an increase in the output of the HCCI engine due to a delay in response of the supercharging pressure in increasing the required output of the HCCI engine in response to a request to charge the electrical storage device, which is not caused by driver's operation.

With the control system according to this aspect, when the transmission device is shifted, a driving force based on the differential output between the required output and the output of the HCCI engine changes, and an output that is generated by the rotary machine in compensation also changes, so there is a possibility that the changed output falls outside the outputtable range of the rotary machine and, as a result, drivability decreases.

However, since a shift of the transmission device is restricted at the time when the output of the rotary machine compensates for the differential output between the required output and the output of the HCCI engine, it is possible to operate the rotary machine within the outputtable range.

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